Despite later overcoming the ring’s influence, he would return to Red Lantern Corps on-and-off, even becoming their leader at one point.
By the time Guy Gardner discovered his alien physiology, he had already attempted to rebrand himself as a new superhero called Warrior, which was also the name of the bar he opened (along with another eatery he started with future Suicide Squad member Blackguard, too).
However, it might not sound too surprising to learn that Gardner has also taken a walk on the dark side by becoming a member of the villainous equivalent to the Green Lantern Corps.
During the Blackest Night arc, the death of Guy Gardner’s Corps partner Kyle Rayner caused him to develop a scathing rage, which happens to be the one emotion which rings from the evil Red Lantern Corps are most attracted to.